﻿// MIT License - Copyright (c) 2016 Can Güney Aksakalli

using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Threading;

namespace UnityGLTF.Examples
{
	class SimpleHTTPServer
	{
		private readonly string[] _indexFiles =
		{
			"index.html",
			"index.htm",
			"default.html",
			"default.htm"
		};

#if !WINDOWS_UWP
		private static IDictionary<string, string> _mimeTypeMappings =
			new Dictionary<string, string>(StringComparer.InvariantCultureIgnoreCase)
			{
#else
	private static IDictionary<string, string> _mimeTypeMappings =
new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase) {
#endif

				#region extension to MIME type list

				{".asf", "video/x-ms-asf"},
				{".asx", "video/x-ms-asf"},
				{".avi", "video/x-msvideo"},
				{".bin", "application/octet-stream"},
				{".cco", "application/x-cocoa"},
				{".crt", "application/x-x509-ca-cert"},
				{".css", "text/css"},
				{".deb", "application/octet-stream"},
				{".der", "application/x-x509-ca-cert"},
				{".dll", "application/octet-stream"},
				{".dmg", "application/octet-stream"},
				{".ear", "application/java-archive"},
				{".eot", "application/octet-stream"},
				{".exe", "application/octet-stream"},
				{".flv", "video/x-flv"},
				{".gif", "image/gif"},
				{".hqx", "application/mac-binhex40"},
				{".htc", "text/x-component"},
				{".htm", "text/html"},
				{".html", "text/html"},
				{".ico", "image/x-icon"},
				{".img", "application/octet-stream"},
				{".iso", "application/octet-stream"},
				{".jar", "application/java-archive"},
				{".jardiff", "application/x-java-archive-diff"},
				{".jng", "image/x-jng"},
				{".jnlp", "application/x-java-jnlp-file"},
				{".jpeg", "image/jpeg"},
				{".jpg", "image/jpeg"},
				{".js", "application/x-javascript"},
				{".mml", "text/mathml"},
				{".mng", "video/x-mng"},
				{".mov", "video/quicktime"},
				{".mp3", "audio/mpeg"},
				{".mpeg", "video/mpeg"},
				{".mpg", "video/mpeg"},
				{".msi", "application/octet-stream"},
				{".msm", "application/octet-stream"},
				{".msp", "application/octet-stream"},
				{".pdb", "application/x-pilot"},
				{".pdf", "application/pdf"},
				{".pem", "application/x-x509-ca-cert"},
				{".pl", "application/x-perl"},
				{".pm", "application/x-perl"},
				{".png", "image/png"},
				{".prc", "application/x-pilot"},
				{".ra", "audio/x-realaudio"},
				{".rar", "application/x-rar-compressed"},
				{".rpm", "application/x-redhat-package-manager"},
				{".rss", "text/xml"},
				{".run", "application/x-makeself"},
				{".sea", "application/x-sea"},
				{".shtml", "text/html"},
				{".sit", "application/x-stuffit"},
				{".swf", "application/x-shockwave-flash"},
				{".tcl", "application/x-tcl"},
				{".tk", "application/x-tcl"},
				{".txt", "text/plain"},
				{".war", "application/java-archive"},
				{".wbmp", "image/vnd.wap.wbmp"},
				{".wmv", "video/x-ms-wmv"},
				{".xml", "text/xml"},
				{".xpi", "application/x-xpinstall"},
				{".zip", "application/zip"},

				#endregion
			};
		private Thread _serverThread;
		private string _rootDirectory;
#if !WINDOWS_UWP
		private HttpListener _listener;
#endif
		private int _port;

		public int Port
		{
			get { return _port; }
			private set { }
		}

		/// <summary>
		/// Construct server with given port.
		/// </summary>
		/// <param name="path">Directory path to serve.</param>
		/// <param name="port">Port of the server.</param>
		public SimpleHTTPServer(string path, int port)
		{
			this.Initialize(path, port);
		}

		/// <summary>
		/// Construct server with suitable port.
		/// </summary>
		/// <param name="path">Directory path to serve.</param>
		public SimpleHTTPServer(string path)
		{
#if !WINDOWS_UWP
			//get an empty port
			TcpListener l = new TcpListener(IPAddress.Loopback, 0);
			l.Start();
			int port = ((IPEndPoint) l.LocalEndpoint).Port;
			l.Stop();
			this.Initialize(path, port);
#endif
		}

		/// <summary>
		/// Stop server and dispose all functions.
		/// </summary>
		public void Stop()
		{
#if !WINDOWS_UWP
			_serverThread.Abort();
			_listener.Stop();
#endif
		}

		private void Listen()
		{
#if !WINDOWS_UWP
			_listener = new HttpListener();
			_listener.Prefixes.Add("http://*:" + _port.ToString() + "/");
			_listener.Start();
			while (true)
			{
				try
				{
					HttpListenerContext context = _listener.GetContext();
					Process(context);
				}
				catch (Exception ex)
				{
				}
			}
#endif
		}

#if !WINDOWS_UWP
		private void Process(HttpListenerContext context)
		{
			string filename = context.Request.Url.AbsolutePath;
			Console.WriteLine(filename);
			filename = filename.Substring(1);

			if (string.IsNullOrEmpty(filename))
			{
				foreach (string indexFile in _indexFiles)
				{
					if (File.Exists(Path.Combine(_rootDirectory, indexFile)))
					{
						filename = indexFile;
						break;
					}
				}
			}

			filename = Path.Combine(_rootDirectory, filename);

			if (File.Exists(filename))
			{
				try
				{
					Stream input = new FileStream(filename, FileMode.Open);

					//Adding permanent http response headers
					string mime;
					context.Response.ContentType = _mimeTypeMappings.TryGetValue(Path.GetExtension(filename), out mime)
						? mime
						: "application/octet-stream";
					context.Response.ContentLength64 = input.Length;
					context.Response.AddHeader("Date", DateTime.Now.ToString("r"));
					context.Response.AddHeader("Last-Modified", System.IO.File.GetLastWriteTime(filename).ToString("r"));

					byte[] buffer = new byte[1024 * 16];
					int nbytes;
					while ((nbytes = input.Read(buffer, 0, buffer.Length)) > 0)
						context.Response.OutputStream.Write(buffer, 0, nbytes);
					input.Close();

					context.Response.StatusCode = (int) HttpStatusCode.OK;
					context.Response.OutputStream.Flush();
				}
				catch (Exception ex)
				{
					context.Response.StatusCode = (int) HttpStatusCode.InternalServerError;
				}
			}
			else
			{
				context.Response.StatusCode = (int) HttpStatusCode.NotFound;
			}

			context.Response.OutputStream.Close();
		}
#endif

		private void Initialize(string path, int port)
		{
#if !WINDOWS_UWP
			this._rootDirectory = path;
			this._port = port;
			_serverThread = new Thread(this.Listen);
			_serverThread.Start();
#endif
		}
	}
}
